Method for guiding in real time a landborne vehicle provided with an off-board navigation system

• US 20050203677A1
• Filed: 03/08/2005
• Published: 09/15/2005
• Est. Priority Date: 03/08/2004
• Status: Active Grant

• Current Assignee: Orange S.A.
• Original Assignee: Orange S.A.
• Inventors: Lemee, Christophe, Magret, Jean-Michel, Auger, Jean-Laurent
• Granted Patent: US 7,590,489 B2
• Time in Patent Office: Days
• US Class Current: 701/16
• CPC Class Codes: G01C 21/34 Route searching; Route guidance

Abstract

The invention relates to a method for guiding a vehicle (Ve) provided with an off-board navigation system relative to an external navigation server (S). It consists in transmitting (A) from the positioning module of the vehicle (Ve) to the server (S) position coordinates of the vehicle, calculating (B) the initial latency time (T1) and the return latency time (T2) between the vehicle and server, estimating (C) the distances covered (X1, Y2) by the vehicle (Ve) during the initial latency time and the return latency time, correcting (D) the position coordinates of the vehicle at the current moment by the value of the covered distances (X1, X2) in order to generate corrected coordinates (XC, YC), and triggering (E) the transmission of a guidance command if the corrected data corresponds to a positioning of the vehicle (Ve) allowing an appropriate reaction of the user of the vehicle. Application in the industry of off-board guidance systems.

Claims

1. Method for guiding in real time a landborne vehicle provided with an on-board navigation system, wherein the navigation and guiding data is processed in a remote manner in a navigation and guiding server external to the vehicle, from an on-board positioning module in this vehicle and communicating information regarding the position of the vehicle to said server, wherein said method consists in at least:

a) transmitting from said positioning module to said server position coordinates of the vehicle at a current moment;

b) calculating, in said server, the initial latency time and the return latency time, the initial transmission time and the return transmission time, respectively, between said vehicle and said server;

c) estimating, from current mapping information corresponding to the current geographical position of said vehicle and from an estimation of the average speed of said vehicle over at least part of an itinerary of said vehicle located relative to this current mapping information, the distance covered by the vehicle during the initial latency time and the return latency time, respectively;

d) correcting said position coordinates of the vehicle at the current moment by the value of the distances covered during the initial latency time and the return latency time, respectively, in order to generate corrected position coordinates;

e) triggering the transmission of a command for guiding said server toward the vehicle if said corrected coordinates correspond to a positioning of the vehicle allowing an appropriate reaction of the user of the vehicle in accordance with the guidance command.

2. Method according to claim 1, and consisting in estimating the average speed of the vehicle between said current moment and a preceding current moment for transmitting the position coordinates of said vehicle.

3. Method according to claim 1, wherein the initial latency time and the return latency time are calculated by means of the time-stamp difference of messages exchanged between the vehicle and the server.

4. Method according to claim 2, wherein the initial latency time and the return latency time are calculated by means of the time-stamp difference of messages exchanged between the vehicle and the server.

5. Method according to claim 1, wherein said corrected position coordinates confirm the equation:

$\{\hspace{1em}<br><br>\begin{array}{c}{X}_0+X_1+X_2=X_C\\ Y_0+Y_1+Y_2=Y_C\end{array}$

wherein (X₀, Y₀) designate the vehicle position coordinates at each current moment;

X₁, Y₁ designate the variations in the position coordinates of the vehicle during the initial latency time;

X₂, Y₂ designate the variations in the position coordinates of the vehicle during the return latency time.

6. Method according to claim 4, wherein the procedure consisting in triggering the transmission of a guidance command from said server to said vehicle is carried out at a given moment allowing coincidence between said corrected coordinates (X_c, Y_c) and the coordinates of a given point (X_T, Y_T) for changing the direction of the vehicle over at least part of a route of the vehicle located relative to the current mapping information

X_C=X_T−

Δ

_XT
Y_C=Y_T−

Δ

_YT,

equations in which Δ

_XT and Δ

_YT represent a guard time.

7. Method according to claim 1, wherein, said on-board positioning module is formed by a GPS terminal, said current moments at which the positioning module transmits the position coordinates of the vehicle are periodic, by a period value that is a multiple of the duration of a GPS frame.

8. Vehicle-external navigation and guiding server, said server receiving position coordinates of the vehicle at one of the current moments and comprising at least one module for adapting mapping information as a function of said position coordinates, a module for calculating the road sheet itinerary steering said mapping adaptation module and a module for guiding said vehicle receiving position information delivered by said information adaptation module and delivering a guidance command on coincidence of the position information delivered by said information adaptation module with position information regarding a change in direction of a route reference relative to said mapping information, wherein said server also comprises a module for calculating the initial latency time and the return latency time, the initial transmission time and the return transmission time, respectively, between said vehicle and said server;

a module for estimating, from current mapping information corresponding to the current geographical position of said vehicle and from an estimation of the average of said vehicle over at least part of a route of said vehicle relative to this current mapping information, the distance covered by the vehicle during the initial latency time and the return latency time, respectively;

a module for correcting said position coordinates of the vehicle at the current moment by the value of the distances covered during the initial latency time and the return latency time, respectively, in order to generate corrected position coordinates, said corrected position coordinates being substituted for position information delivered to said guiding module, thus allowing the transmission of a guidance command to be triggered from said server to the vehicle if said corrected coordinates correspond to a positioning of the vehicle allowing an appropriate reaction of the user of the vehicle in accordance with the guidance command.

9. Server according to claim 8, wherein said module for calculating the latency time comprises at least means for storing the average speed of the vehicle over at least one period of time separating the current moment and a preceding current moment.

10. Server according to claim 8, wherein said module for calculating the latency time also comprises means for selecting the moment for transmitting the guidance command from said server to said vehicle, as a function of the average speed of said vehicle.

11. Server according to claim 9, wherein said module for calculating the latency time also comprises means for selecting the moment for transmitting the guidance command from said server to said vehicle, as a function of the average speed of said vehicle.